Master Redis Data Types with Python: Strings, Lists, Sets, Sorted Sets, and Hashes

1. Strings

Python redis module provides the following string operations: SET, GET, GETSET, SETEX, SETNX, MSET, MSETNX, INCR (including INCRBY, DECR, DECRBY), APPEND, SETRANGE, STRLEN.

SET : set(self, name, value, **kwargs)

GET : get(self, name)

GETSET : getset(self, name, value)

SETEX : setex(self, name, value, time)

SETNX : setnx(self, name, value)

MSET : mset(self, mapping)

MSETNX : msetnx(self, mapping)

INCR : incr(self, name, amount=1) – supports INCRBY, DECR, DECRBY via amount

APPEND : append(self, key, value)

SETRANGE : setrange(self, name, offset, value)

STRLEN : strlen(self, name)

Example code:

#!/usr/bin/python
# -*- coding:utf-8 -*-
# __author__ = 'Jack'

pool = redis.ConnectionPool(host='127.0.0.1', port=6379)
r = redis.Redis(connection_pool=pool)
r.flushall()  # clear Redis

r.setex('name', value='liaogx', time=2)  # set new value with 2s expiration
r.mset(k1='v1', k2='v2', k3='v3')  # batch set
print(r.mget('k1', 'k2', 'k3', 'k4'))  # batch get
print(r.getset('name', 'liaogaoxiang'))  # set new value and get old
print(r.getrange('name', 0, 1))  # get substring
r.setrange('name', 0, 'LIAO')  # modify string from offset

i = 0
while i < 4:
    print(r.get('name'))
    time.sleep(1)
    i += 1
source = 'foo'
r.set('n1', source)
r.setbit('n1', 7, 1)
print(r.get('n1'))
print(r.getbit('n1', 7))
r.set('n2', '廖高祥')
print(r.strlen('n2'))
r.set('num', 1)
r.incr('num', amount=10)
r.decr('num', amount=1)
print(r.get('num'))
r.append('num', 111)
print(r.get('num'))

Output:

[b'v1', b'v2', b'v3', None]
b'liaogx'
b'li'
b'LIAOgaoxiang'
b'LIAOgaoxiang'
b'LIAOgaoxiang'
b'LIAOgaoxiang'
b'goo'
1
9
b'10'
b'10111'

2. Lists

Redis list commands are wrapped by the redis module as: LPUSH, LRANGE, LINDEX, BLPOP, BRPOP. Functions are described below.

LPUSH lpush key value – push value to the head of the list.

LRANGE lrange key start end – get elements in the specified range.

LINDEX lindex key index – get element by index.

BLPOP – pop first element from the left (blocking).

BRPOP – pop first element from the right (blocking).

LPUSHX, RPUSHX – not implemented in the current version.

Example code:

#!/usr/bin/python
# -*- coding:utf-8 -*-
# __author__ = 'Jack'

pool = redis.ConnectionPool(host='127.0.0.1', port=6379)
r = redis.Redis(connection_pool=pool)
r.flushall()

r.lpush('oo', 11)  # list becomes: 11
r.lpushx('oo', 0)  # only works if list exists
print(r.llen('oo'))  # length

r.linsert('oo', 'before', 11, 99)  # insert 99 before 11
r.lset('oo', 1, 88)  # set index 1 to 88
print(r.lrange('oo', 0, -1))

r.lrem('oo', 88, num=1)  # remove one occurrence of 88
print(r.lrange('oo', 0, -1))

print(r.lpop('oo'))  # pop leftmost element
print(r.lindex('oo', 0))

r.lpush('l1', 11)
r.rpush('l1', 22)
r.rpush('l1', 33)
r.rpush('l1', 44)
r.rpush('l1', 55)
r.ltrim('l1', 1, 3)  # keep indices 1‑3
print(r.lrange('l1', 0, -1))

r.rpoplpush('l1', 'l1')
print(r.lrange('l1', 0, -1))

r.brpoplpush('l1', 'l1', timeout=3)
print(r.lrange('l1', 0, -1))

print(r.blpop('l1', 3))
print(r.lrange('l1', 0, -1))

def list_iter(name):
    list_count = r.llen(name)
    for index in range(list_count):
        yield r.lindex(name, index)

for item in list_iter('l1'):
    print(item)

Output (excerpt):

2
[b'0', b'88', b'11']
[b'0', b'11']
b'0'
b'11'
[...]

3. Sets

Redis set commands are wrapped as: SADD, SCARD, SDIFF, SDIFFSTORE, SINTER, SINTERSTORE, SISMEMBER, SMEMBERS, SMOVE, SPOP, SRANDMEMBER, SREM, SUNION, SUNIONSTORE, SSCAN.

SADD : sadd(self, name, value)

SCARD : scard(self, name)

SDIFF : sdiff(self, keys, *args)

SDIFFSTORE : sdiffstore(self, dest, keys, *args)

SINTER : sinter(self, keys, *args)

SINTERSTORE : sinterstore(self, dest, keys, *args)

SISMEMBER : sismember(self, name, value)

SMEMBERS : smembers(self, name)

SMOVE : smove(self, src, dest, value)

SPOP : spop(self, name)

SRANDMEMBER : srandmember(self, name)

SREM : srem(self, name, value)

SUNION : sunion(self, keys, *args)

SUNIONSTORE : sunionstore(self, dest, keys, *args)

SSCAN : sscan(self, name, cursor=0, match=None, count=None)

Example code:

#!/usr/bin/python
# -*- coding:utf-8 -*-
# __author__ = 'Jack'

pool = redis.ConnectionPool(host='127.0.0.1', port=6379)
r = redis.Redis(connection_pool=pool)
r.flushall()

r.sadd('s1', 'v1', 'v1', 'v2', 'v3')
r.sadd('s2', 'v2', 'v4')
print(r.scard('s1'))
print(r.sdiff('s1', 's2'))

r.sdiffstore('s3', 's1', 's2')
print(r.smembers('s3'))

print(r.sinter('s1', 's2'))
r.sinterstore('s4', 's1', 's2')
print(r.smembers('s4'))

print(r.sunion('s1', 's2'))

r.sunionstore('s5', 's1', 's2')
print(r.smembers('s5'))

print(r.sismember('s4', 'v4'))

r.smove('s2', 's1', 'v4')
print(r.smembers('s1'))

r.srem('s1', 'v1')
print(r.spop('s1'))
print(r.srandmember('s1'))

Output (excerpt):

3
{b'v3', b'v1'}
{b'v3', b'v1'}
{b'v3', b'v1'}
{b'v3', b'v2', b'v4', b'v1'}
False
{b'v3', b'v2', b'v4', b'v1'}
b'v2'
b'v2'

4. Sorted Sets

Redis sorted‑set commands include ZADD, ZCARD, ZCOUNT, ZINCRBY, ZINTERSTORE, ZLEXCOUNT, ZRANGE, ZRANGEBYLEX, ZRANGEBYSCORE, ZRANK, ZREM, ZREMRANGEBYLEX, ZREMRANGEBYRANK, ZREMRANGEBYSCORE, ZREVRANGE, ZREVRANGEBYSCORE, ZREVRANK, ZSCORE, ZUNIONSTORE, ZSCAN.

Example code:

#!/usr/bin/python
# -*- coding:utf-8 -*-
# __author__ = 'Jack'

pool = redis.ConnectionPool(host='127.0.0.1', port=6379)
r = redis.Redis(connection_pool=pool)
r.flushall()

r.zadd('z1', '11', 1, '22', 2, '33', 3, '44', 4, '55', 5, '66', 6, '66', 7)
print(r.zcard('z1'))
print(r.zcount('z1', 1, 2))
r.zincrby('z1', '11', amount=5)
print(r.zrange('z1', 0, -1, desc=False, withscores=True))

print(r.zrank('z1', 33))

r.zrem('z1', '66')
print(r.zrange('z1', 0, -1, desc=False, withscores=True))

r.zremrangebyrank('z1', 0, 1)
print(r.zrange('z1', 0, -1, desc=False, withscores=True))

r.zremrangebyscore('z1', 4.5, 5.5)
print(r.zrange('z1', 0, -1, desc=False, withscores=True))

print(r.zscore('z1', 11))

r.zadd('zset_name', 'a1', 6, 'a2', 2, 'a3', 5)
r.zadd('zset_name1', a1=7, b1=10, b2=5)
r.zinterstore('zset_name2', ('zset_name', 'zset_name1'), aggregate='Sum')
print(r.zrange('zset_name2', 0, -1, desc=False, withscores=True))

Output (excerpt):

6
2
[(b'22', 2.0), (b'33', 3.0), (b'44', 4.0), (b'55', 5.0), (b'11', 6.0), (b'66', 6.0)]
1
[(b'22', 2.0), (b'33', 3.0), (b'44', 4.0), (b'55', 5.0), (b'11', 6.0)]
[(b'44', 4.0), (b'55', 5.0), (b'11', 6.0)]
[(b'44', 4.0), (b'11', 6.0)]
6.0
[(b'a1', 13.0)]

5. Hashes

Redis hash commands are wrapped as: HDEL, HEXISTS, HGET, HGETALL, HINCRBY, HKEYS, HLEN, HMGET, HMSET, HSET, HSETNX, HVALS, HINCRBYFLOAT.

HDEL : hdel(self, name, key)

HEXISTS : hexists(self, name, key)

HGET : hget(self, name, key)

HGETALL : hgetall(self, name)

HINCRBY : hincrby(self, name, key, amount=1)

HKEYS : hkeys(self, name)

HLEN : hlen(self, name)

HMGET : hmget(self, name, keys)

HMSET : hmset(self, name, mapping)

HSET : hset(self, name, key, value)

HSETNX : hsetnx(self, name, key, value)

HVALS : hvals(self, name)

HINCRBYFLOAT : hincrbyfloat(self, name, key, amount=1.0)

Example code:

#!/usr/bin/python
# -*- coding:utf-8 -*-
# __author__ = 'Jack'

pool = redis.ConnectionPool(host='127.0.0.1', port=6379)
r = redis.Redis(connection_pool=pool)
r.flushall()

r.hset('n1', 'k1', 'v1')
print(r.hget('n1', 'k1'))

r.hmset('n2', {'k1':'v1','k2':'v2','k3':'v3'})
print(r.hmget('n2', 'k2'))
print(r.hgetall('n2'))
print(r.hlen('n2'))
print(r.hkeys('n2'))
print(r.hvals('n2'))
print(r.hexists('n2', 'k4'))

r.hdel('n2', 'k3')

r.hset('n3', 'k1', 1)
r.hincrby('n3', 'k1', amount=1)
print(r.hgetall('n3'))

Output:

b'v1'
[b'v2']
{b'k1': b'v1', b'k2': b'v2', b'k3': b'v3'}
3
[b'k1', b'k2', b'k3']
[b'v1', b'v2', b'v3']
False
{b'k1': b'2'}

For a complete reference of Redis commands, see the official Redis documentation.